We perform the first dipole picture fit to HERA inclusive cross section data using the full next-to-leading order (NLO) impact factor combined with an improved Balitsky-Kovchegov evolution including the dominant effects beyond leading logarithmic accuracy at low x . We find that three different formulations of the evolution equation that have been proposed in the recent literature result in a very similar description of HERA data and robust predictions for future deep inelastic scattering experiments. We find evidence pointing toward a significant nonperturbative contribution to the structure function for light quarks, which stresses the need to extend the NLO impact factor calculation to massive quarks.
Physical Review D
- Pub Date:
- October 2020
- High Energy Physics - Phenomenology;
- Nuclear Theory
- 20 pages, 9 figures. v2: matches published version. Fit results available at https://doi.org/10.5281/zenodo.4229269